Three-area vane type fluid pressure energy translating devices



Dec. 14, 1965 Filed July 18, 1963 THREE-AREA E. ADAMS ETAL VANE TYPE FLUID PRESSURE ENERGY TRANSLATING DEVICES 4 Sheets-Sheet 1 INVENTORS. CECIL E. ADAMS GERALD E. DE VILLERS bmu W Dec. 14, 1965 Filed July 18, 1963 c. E. ADAMS ETAL 3,223,044

THREE-AREA VAN YPE FLUID PRESSURE ENERGY TR LATING DEVICES 4 Sheets-Sheet 2 INVENTORS.

@w/y W Dec. 14, 1965 ADAMSFEIEAL 3,223,044

THREE-A VANE T D PRESSURE ENERGY TRANSL ING DEVICES Filed July 18, 1965 4 Sheets-Sheet 5 INVENTORS. CECIL E. ADAMS GERALD E. DE VILLERS Dec. 14, 1965 c. E. ADAMS ETAL 3,223,044

THREE-AREA VANE TYPE FLUID PRESSURE ENERGY TRANSLATING DEVICES Filed July 18, 1963 4 Sheets-Sheet 4 INVENTORS. CECIL E. ADAMS GERALD E. DE VILLERS United States Patent 3,223,044 TImEE-AREA VANE TYPE FLUID PRESSURE ENERGY TRANSLATING DEVICES Cecil E. Adams and Gerald E. De Viilers, Columbus, Ohio, assignors to American Brake Shoe Company, New York, N.Y., a corporation of Delaware Filed .luly 18, 1963, Ser. No. 296,017 11 Claims. (Cl. 103-136) This invention is directed to improvements in fluid pressure energy translating devices of the vane type, and more specifically it relates to improvements in vane pumps or motors of the type which include hydraulic means for vane control.

Fluid pressure energy translating devices of the vane type include a rotary member or rotor having a plurality of radially movable vanes carried in slots equidistantly spaced around its periphery. These vanes engage the inner or cam surface of a fixed stator or cam ring which surrounds the rotor. Inlet and outlet ports open at spaced positions into the area between the periphery of the rotor and the inner surface of the cam ring and are swept or traversed sequentially by the vanes as the rotor turns. Fluid is received at the inlet port and is transferred by the vanes to the outlet port. Depending on whether the rotor is driven by a prime mover or whether the rotor is caused to be rotated by a greater pressure at the inlet port than at the outlet port, the device constitutes either a pump or motor.

One object of this invention is to provide improved means for maintaining a fluid seal between the outer ends or edges of the vanes and the inner surface of the cam ring, to prevent or minimize fluid leakage from an area of higher pressure on one side of a vane to an area of lower pressure on the other side of the vane, and to maintain the outer ends of the vanes in sealing engagement with the inner surface of the cam ring as the vanes and rotor rotate, regardless of irregularities in the contour or arcuateness of the cam ring surface and without undue wear on the latter.

It is another object of this invention to provide means in a fluid pressure energy translating device of the vane type having hydraulic means urging the vanes outwardly in their slots as set forth in the foregoing object in which fluid under pressure is fed to the hydraulic means through passageways which do not include rotary joints such, for example, as clearance gaps between the rotor and cheek plates or end blocks through which fluid under pressure can escape to reduce the volumetric efliciency, etc., of the device.

It is another object of this invention to provide the foregoing means in fluid pressure energy translating devices having three area type vane control.

In vane type pumps and motors of the three area type fluid pressures act on three areas associated with each vane, and the forces resulting from these pressures cooperate to urge each vane into engagement with the cam surface with a predetermined desired force.

The pressure acting on two of the areas associated with each vane are substantially equal but act in opposite directions, and the forces resulting from these pressures tend to counteract each other. The first area comprises a surface on the radially outer end of the vane and is subjected to pressure which urges the vane inwardly in its slot. The second vane area is a vane area which is subjected to a pressure opposed to that acting on the first area, and urges the vane outwardly in its slot.

The third area is also subjected to pressure which urges the vane outwardly in its slot. It is the pressure on this third area which, excepting centrifugal force, provides the controlling force urging the vane outwardly to effect a fluid seal between the outer end of the vane and the cam ring and to maintain the outer end of the vane in sealing engagement with the cam ring surface regardless of irregularities in the contour or arcuateness of the win ring surface.

The three area vane control principle is utilized to provide an outwardly directed force of predetermined desired magnitude which is applied to each vane to obtain and maintain engagement between the vane and the cam ring surface. By utilization of the three area vane control principle a predetermined force for urging or moving the vanes outwardly is obtained and this force can be obtained in devices wherein the vanes are urged outwardly by springs.

The basic principles of the three area concept for controlling vanes are taught in Cecil E. Adams et al. US. Patent No. 2,832,293 for Vane Pump. According to one form of a three area device as disclosed in the Adams et al. patent, there is associated with each vane a piston mounted in the rotor for sliding movement in the radial direction to engage the inner end of the vane. Fluid under pressure for operating the several pistons is supplied through a channel or chamber in the rotor adjacent the operating shaft which in turn is fed through grooves formed in the cheek plate surfaces adjacent the rotor and leading from the high pressure zone. Because the fluid being fed to the rotor channel must pass from or through the cheek plates across the clearance gaps between the rotor and cheek plate, considerable quantities of fluid and pressure can escape through the clearance gaps. This loss reduces the overall eflic'iency of the device.

Prior to this invention, no satisfactory means had been known for supplying fluid under pressure to the third area means from which excessive amounts of fluid could not leak or otherwise escape. As previously suggested, one object of this invention includes the provision of a pump or motor including the three area vane control principle in which the passageway means through which fluid under pressure is supplied to the third area means is contained wholly within the rotating assembly including the rotor body and is not exposed to leakage paths (such as the mentioned clearance gaps) from which leakage of high pressure fluid from the high pressure fluid passageway can occur.

The further objects and advantages of the present invention will be apparent from the following description, reference being made to the accompanying drawings wherein a preferred embodiment of the invention is disclosed.

In the drawings:

FIGURE 1 is a vertical longitudinal or axial sectional view of a three-area vane type fluid pressure energy translating device including the invention;

FIGURE 2 is a view in section taken on line 22 of FIGURE 1 and showing the relative positions of the ports;

FIGURE 3 is a view in section taken on line 3-3 of FIGURE 2 showing particularly the arrangement of the suction or inlet ports;

FIGURE 4 is a view in elevation of the movable head, port plate, or cheek plate of the device seen in FIGURE 1, the view showing particularly the fluid ports and passageways therein;

FIGURE 5 is a view in elevation of the end cap or block of the device seen in FIGURE 1, the view showing particularly the fluid ports and passageway therein;

FIGURE 6 is a transverse section of a rotor and stator assembly showing a second embodiment of the invention;

FIGURE 6A is a view taken on line 6A6A of FIG- URE 6B;

3 FIGURE 6B is a view taken on line 6B6B of FIG- URE 6 but on a larger scale;

FIGURE 7 is an axial section through a rotor assembly showing still another embodiment of the invention; and FIGURE 8 is a view in section of apart of a rotor; cam ring, vane and piston element, the assembly having springs positioned between the rotor and a vane thereincludes a body, casing or housing formed by a'casting or body section 20'having a generally cylindrical hollow interior and an end cap or block 21 having a cylindrical boss 22 which telescopes into the open end of the body 20 and 'is sealed thereto; by' an' O-ring 23' received 'in a groove in the body 20. The end cap 21 is secured to the body 20 by four screws, one-of'which is seen in FIGURE 1, and may be rotated to and secured inany one of four angular positions with respect'to'the body 20. By this arrangement the relative radial or rotated positions of an inlet, low pressure or suction port 24' in the body 20 and a high pressure, exhaust or 'outlet'port 25 in the end cap 21 may be changed with respect to one another.

The end wall 26' of the body 20 opposite the cap 21 includes a borexthroughwhich the pump operating shaft 27 extends. Shaft. 27 is supported for rotation in this 'bo're bya ball bearing 28 which is secured against axial movement in the bore 'by a'fiange29 on'the casting and a snap ring 30- which is received in a groove in the bore.

The end of the shaft 27 which is within the housing is carried for rotation in a hee'dle type roller" bearing 31 mated within a central bore or recess in the end cap 21.

Boss-22 of the end'cap 21 is finishedto form a fiat check or port plate surface' which abuts 'a flat endsur'face-of a cam ring 32. 'Itmay' be mentioned here'that the "casing or housing and the cam ring are frequently termed in .the art'as the stator,-a'n'd frequently the cam ring per 'se is termed the stator. It will therefore be understood that the term stator as employed in the claims hereof is to be' construed as meaning the combination of the housing and the cam ring, the cam ring itself, or the equivalent elements in any unit wherein thehousing and stator are made integral as is sometimes done in the art.

The fluid intake port 24 extends radially inward and communicates with apair of internal :annular' grooves or channels 37, 38 formed within the body 20,'as shown in FIGURE 1, which encircle the internal cavity within the body. The channels '37, 38 distribute fluid from the intake port 24 to pumping spaces to be described. The cam ring 32 is supported radially by an annular rib 40 formed in the body 20 between the channels 37, 38.

The cam ring 32 encircles or encompasses a rotor 42 whi ch is mounted upon the shaft 27 for relative 'axial movement through a relatively loose splined joint connection which'will allow proper running alignment between the rotor and the adjacent cheek plates. The'width 'of rotor 42 is no greater thanand is preferably of the order of .0015 inch less than the axial dimension of the cam ring 32 in order that it may rotate without undue friction against the surface of boss 22 on one side and the face of a floating cheek plate 43, which will be described in'detail hereinafter, on the other side. The rotor 42 is provided-with a plurality of radially extending vane slots in each of which there is a vane 45. Each vane 45 is urged radially outwardly against the inner surface 46 of cam ring 32 by means to be described.

The cam ring 32 has a cylindrical external surface, and its interior surface 46 provides a balanced type construction in which there are diametrically opposite pairs of low pressure, suction or inlet zones, 47, fluid transfer zones 48, high pressure or exhaust zones 49, and sealing zones 50 (see FIG. 2). In order to provide these opposed pairs of zones, the interior or cam surface 46 of cam ring 32 is formed in part upon two arcs 51 of equal radii struck from theaxis of shaft'27, which extend'across the transfer zones 48, and two' arcs 52 of shorter radii than the first mentioned arcs and which extend across the sealing zones 50. The arcs 52 are substantially or 'nearly' tangent to the rotor 42. The arcs 51 -and 52'are connected by cam portions or surfaces '53 and 54, which extend across the low pressure zones 47 'and high pressure zones 49 respectively.

The cheek plate 43 is finished to a smooth flat surface 58 onthe side thereof which abuts the cam ring '32, and is provided with a central bore 59 surrounded by a cylindrical boss 61 which extends to the bore in'the end wall 26 of the body 20 and is sealed thereto by an O- ring 62 contained in a groove in the body. The central bore in the cheek plate 43 receives an oil seal '63 which engages the shaft 27 and prevents the loss of fluid to the outside of the body or housing of the pump, and which also prevents the entrance of air into the interior of the body. The radially outermost cylindrical peripheral surface of cheek plate 43 is sealed to the body 20 by means ofan O-ring 65.

The cheek" plate 43 is urged axially toward the rotor 42 by the action of fluid pressure directed from'fiuid discharge ports within the pump through passageways 66 land 82'to an annular space or pressure chamber 68 formed between the body and the outer face of the cheek plate. The cheek plate 43 functions in the nature of an axially movable, non-rotatable piston under the pressure supplied by fluidin chamber 68.

Pins 70- (FIGURE 2) extend into bores formed in the cam ring 32, the end cap 21, and the cheek plate 43.

The pins 70 in theirrespective bores function to align these elements when the pump is being assembled and to prevent rotation of the cheek plate '43 during operation. The pins 70 and their bores are so arranged that the cam ring 32 may be held between the-end cap 21 and the cheek plate 43 in either of two positions separated by in angular relation, one providing for'clockwise rotation of the shaft 27 and the other providing for its counterclockwise rotation.

When the pump is operating, fluid flows from the inlet or suction port 24, through the grooves 37, 38 and circumferentially around the cam ring 32 to two ports j spaced 1apart,'at which the fluid flows axially 'and around the cam ring 32 and enters inlet or suction ports 72 formed in cheek plate 43 and inlet or suction ports 73 formed in the end cap 21 (see FIG. 3). The ports 72 and 73 are axiallyaligned and are identical "in shape. Each pair of ports 72, 73 opens intoa suction Zone 47 adjacent a cam portion 53 of the cam ring 32 when'the cam ring is in the position shown in FIGURE 2 of the drawings. When the cam ring is rotated 90 to provide for the reverse rotation of the shaft 27, the'pressure zones 49 become the suction zones and the ports 72 and 73 open into them. .The ports 72 and 73' each join radially inwardly extending passages which terminate in axially alignedports 74. The ports 74' communicate with the inner ends 86 ofthe vaneslots in the rotor 42 as 'the slots pass the ports 74.

As shown in FIGURES 1 and 3 the end cap 21 includes two crescent-shaped high pressure or exhaust ports 76 which are spaced 180 apart and'at 90 with respect to each of the inlet or suction ports 73. Similarly, high pressure ports 77 are formed infthe cheek plate 43, also of crescent shape and'axially aligned with the'ports 76 "in theend cap. Ports 76'and 77 openinto the pressure zones 49 adjacent the cam portions 54 of cam ring 32.

Each of the ports 76 and 77 also includes a radial inward extension which terminates in a port 78 that communicates with the inner ends 86 of the vane slots in the rotor 42 as the slots pass ports 76 and 77. The ports 76 and 77 are connected with the exhaust, high pressure or outlet port 25 by a passageway 79 in the end cap 21.

The large intake port 24 provides for free, unthrottled flow of fluid into the two annular channels 37, 38 from which fluid flows with equal freedom around the opposite sides of the cam ring through the two pairs of intake ports 72 and 73, so that the pump is enabled to operate at a high volumetric rate without cavitation.

With reference to FIGURE 2, it will be noted that the cam surface 46 comes into close proximity to the rotor 42 in the two diametrically opposed arcuate sealing zones 50 in which the cam surface has a substantially constant radial spacing from the rotor. At the inlet ports 72 and 73, the cam surface 46 progressively recedes from the rotor periphery in the direction of vane movement. In the transfer zones 48, the cam surface 46 also has a substantially constant radial spacing from the rotor, and adjacent the high pressure ports 76 and 77, the cam surface 46 progressively approaches the rotor, until it again comes into close proximity to the rotor in the sealing zones 50. Thus, fluid is drawn into the spaces or fluid transfer pockets between the successive vanes as those spaces become larger when the vanes move through low pressure zones 47, and it is displaced positively as those spaces contract when the vanes move through high pressure zones 49, to eflect a pumping action.

The check plate 43 is provided with radial or transverse passageways 82 which communicate between the high pressure port 77 formed in the cheek plate and the axial passageways 66 formed therein. Through these passageways 82 and 66 fluid at the outlet pressure of the pump is conducted to the chamber 68 on the outer side of the cheek plate whereby a fluid force acts on the cheek plate to hold it in sealing engagement with the cam ring 32. Such floating cheek plates are known in the art, and do not comprise a part of this invention. Their use is preferable, but not absolutely necessary in devices incorporating the principles of this invention.

To effect an eflicient pumping action, it is necessary to maintain continuous engagement of the vanes 45 with the cam surface 46, regardless of changes in the arcuateness of the cam surface due to manufacturing irregularities. Discontinuities in the engagement of the individual vanes with the cam surface 46, or intermittent separation of the vanes from the cam surface 46, are not only a cause of inefficient pumping but can cause serious premature wear on the pumping structure. Specifically, any slight radially outward irregularity in contour throughout the lengths of the arcs 51 or 52 which define the transfer zones 48 and sealing zones 58 may cause separation between the tip of a vane in those sections and the cam surface 46, permitting leakage of fluid from one circumferential side of the vane to the other, unless the vane is urged outwardly with sufficient force to overcome any sticking or friction in its slot whereby it will remain in engagement with the cam ring.

With reference to FIGURE 2, for example, at the rotor position shown, each of the vanes 45 is exposed to high pressure on its forward face and low pressure on its trailing face. This pressure unbalance in the circumferential direction tends to lock the vane 45 in its slot, and a large radial force is required to move the vane against the cam surface 46 at that position should the contour of the cam ring change even in a very small degree. However, unless there is sealing between the edge of vane 45' and cam surface 46, fluid at high pressure on the forward side of the vane will blow over the vane into the zone of low pressure on its opposite side, thereby disturbing the intake flow of fluid at the suction port and in the suction zone 48 and reducing volumetric efiiciency.

6 Moreover, the operation of the pump will be excessively or undesirably noisy.

To prevent these effects, it is essential that when any vane is moving through a transfer zone 48, it be urged outwardly with suflicient force to maintain engagement of its outer edge with the cam surface 46 regardless of cam surface irregularities. However, when a vane is moving across a pressure port 76, 77, i.e. when its edge is moving on the cam surface 54, it is progressively moved inwardly and is not then subjected to a substantial pressure differential in the circumferential direction requiring tight sealing against the cam surface. Hence, the outward force required to maintain a vane in engagement with the cam surface as the vane moves through the transfer zones may be excessive if applied to the vane as it moves on cam surface 54, and can cause excessive wear on both the vanes and on the co-acting cam ring structure.

As shown in FIGURES 1-3, in a preferred embodiment of the invention each of the vanes 45 is provided with grooves 84 which are formed between its side faces along opposite sides and outer ends of the vane. These grooves 84 insure that the fluid pressures acting on the exposed radially opposed end surfaces of the vane will be substantially equal at all times, pressure on the upper end of the vane being reflected through the grooves 84 into the enlarged rounded inner end 86 of the vane slot.

One or more radial bores 88 is formed in the rotor 42 at the inner end of each vane slot. The bores 88 communicate at their inner ends with an annular passageway or groove 89 which extends completely around the rotor 42, and which is sealed with respect to the shaft 27 S0 that fluid can flow either into or out of passageway 89 only through the bores 88.

Passageway 89 can conveniently be sealed by a hollow cylindrical sleeve 90 which is sealingly pressed into a recess in the rotor bore. Power is transferred by a spline connection to shaft 27 as at 91. By this passageway 89 the inner ends of the bores 88 are in constant fluid communication, and are at the pressure of fluid in passageway 89.

In each bore 88 there is provided a tubular piston valve element 92 which is generally cylindrical and which includes an internal bore 93. Each valve element 92 is slidable in its bore 88 but is closely fitted thereto so that leakage of fluid along the walls of the element 92 is minimal. The outer end of each piston element 92 is relieved or conically tapered as at 94, and forms a valve with the flat inner end 95 of the vane 45 which regulates the admission of fluid to bores 88 and passageway 8-9. As previously mentioned, there may be one or more pistons 92 provided to act on each vane, each residing in a bore formed in the rotor and communicating with a passageway 89. The length of valve element 92 is such as to permit it to move into and out of engagement with the flat surface 95 of the vane 45.

In the operation of the pump the valve elements 92 function in the manner of check valves. Whenever, the pressure at the inner end 86 of a given vane slot, which pressure acts upon the outer end of the valve element 92, exceeds sufliciently the pressure in passageway 89 acting on the inner end of the valve element 92 to urge the element toward the vane, valve element 92 is moved inwardly in its bore 88, opening the valve 94, 95 so that fluid in the vane slot flows inwardly to the passageway 89 to restore, maintain or increase the pressure in passageway 89. This action can occur whenever the vane slot registers or connects with a high pressure zone such as a zone 49-78 adjacent a pressure port 78. The pressure at the pressure zones 49-78 is usually the highest in the pump and the pressure in the passageway 89 is usually lower by some amount than the pressure in the ports 78.

By the above described action of the piston valve elements 92, the pressure in passageway 89 is maintained substantially constant for any given pressure at the presshowniriA'dams' et a1. Patent No. 2,832,293.

sure ports 78. When a giv'en'vane is aligned with a suction port 74, the pressure in passageway 89 exceeds the pressure at the outerend of the element'92 associated with that va'ne, and the element is held against the bottom "95 of the'vane to close valve '94, 95, and fluid cannot i the cam ring. a

From the foregoing it will be seen that third area means associated with each va'ne are provided which are adapted to be exposed to'fluid under pressure'to urge the vanes outwardly, and that these means are interconnected by 'means including the passageway 89. The interconnecting passagewaymeans include a portion in the form of the vane slot ends 86 which register or connect with a high pressure zone 49-78 as they rotate past the pressure port as the rotor rotates, and the valves 94, 95 open to admit pressure through these passageway means to the piston elements from the pressure port.

Excepting when a vane is at a pressure zone 4978, force for holding a vane outward is supplied by pressure acting on the endarea of the element 92 and on the vane in the bore "93 which together constitute a third area means. This force varies with thepressure difference at opposite ends-of each element 92, which in turn varies with the position of the vane in relation to the suction and pressure ports.

The pressure differential which acts on the piston valve elements 92 tending to hold them against the inner ends of the vanes is atfected by the area of the relieved end portion 94 of the piston element, and by centrifugal force as a result of the speed of the rotor.

It should be noted that two or more piston valve elements92 may be used to apply greater'force to each vane to apply a larger radial force to the vane.

One important advantage-afforded by the construction shown in FIGURES 1 and 2 is that the valves 94, 95 arespeedresponsive; that'is, they automatically reduce fluid force applied to the third area as speed of rotor rotation increases so as to offset increasing centrifugal force acting on the vanes. T he centrifugal force amen the elements 92 and adds to thefiuid force tending to close the valves 94, 95;the greater thespeed of rotation of the rotor, the greater the centrifugal component of total force 'tending'to close the valves94, 95. This greater mechanical valve closing force requires a greater pressure differential to open the valves94, 95, withthe result that" the pressure in passageway '89 is relatively reduced at'higher operating speeds and the fluid force component of the total force acting on the valve elements 92 is thereby 'reduced. Centrifugal force being greater at higher speeds of operation, there is no need for as high a fluid force to be applied to'the elements 92, and this mode of action te'n'ds'to limit excessive forces acting on the vanes at high speeds of operation.

We recognize that fluid pressure operated piston means have previously been used to apply fluidforceto hold vanes in contactwiththe cam ring. Such means are However, in the three area structure disclosed in that patent, there is no valving'acti'on controlling admittance of pressure to 'oper'atethei pistons. Also, fluid is introduced into the chamber at the inner ends of the pistons across clearance 'gaps'between the rotor'and cheek plateson each "*a'c'ross a'clearance gap or the like, and an important'cause 8 of fluid leakage is thereby obviated. In'addition, the third area force applied by the structure of the Adams et al. patent increases with speed,whereas'in the embodi- Iment described the effect is the opposite.

Those skilled in the art will realize that the particular construction shown in FIGURES 1, 2, and 3 of the drawings is not the only practical way of incorporating the principles of this invention in a pressure energy translating device. By'way of example, other practical constructions are shown in FIGURES 6 and 7. I

In the construction shown in FIGURES 1-5' the piston valve elements'92 are'm'ounted in bores in the rotor and form poppet type check valves with the inner ends of the vanes. Fluid under pressure for all the third' area means is distributed to them through'an' annular conduit .at the inner ends ofthe'valve elements. The vane elements shownare of the double-lip type wherein two sealing surfaces, defined by the groove 84 which extends across the top'and on the side ends of the vanes, can engage the cam surface. It is to be understood that the vanes do not need to be of the double-lip type described, but that any type of' pressure balanced vane may be employed.

In'FIGURES 6, 6A and 6B there is shown structure which diifers from that previously described and which also includes the'features of the'invention. In this embodiment the vanes are of'the single-lip type'and the third area means or vale elements are slidablymounted in the vanes rather than in the rotor. In this' construction, each valve element forms a valveat its inner end with the inner end' of the vane slot. Fluid for operating the third area means is supplied through bores in the rotor between the fluid transfer pockets and the inner ends of the vane slots. The effective third area on which fluid pressure acts to hold the vane outwardly is in the vane opposite a valve element therein and it is equal in area to the'peripheral crosssectional area of the valve element. As seen in FIGS. 6A and 6B this third area is contained within a pressure chamber formed by a pocket in the vane, the side walls of'the vane slot in the rotor andthe valve element. I v

In FIGURE 6', the camrin'g or stator has a cam surface 106 which is of the configuration previously described. The rotor 107 is connected to a shaft 108; and

has vane slots 110 formed therein and'equally spaced around its periphery.

It'may be mentioned here that the rotor 107, as herein shown, is assembled from a pair of identical elements 113 and 114 welded together along the line 117.

Each vane slot 110 is enlarged at its inner end as at 111, and has a generally flat bottom surface 112 which forms a valve with valve elements, as will be described. Diagonal bores 115 communicate between the periphery 116 of the rotor and the chambers 111 of the vane slots. Through these bores 115 the pressure in each chamber 111'is balanced with that in the fluid transfer pocket with which the'particular bore 115 communicates.

The vanes 119 mounted in the vane slots 110'are of the single-lip type, each'vane having'a single surface or lip 120 which engages the cam surface 106. Vanes having a-single cam-ring engaging 'lip 'are well known, and may be used in the practice of'this invention in any of the various alternative constructions described herein.

Each vane 119 is movable radially in its slot 110 and is fitted closely thereto so as to minimize loss of fluid along the sides of the vane to the'periphery of the rotor. Each vane has a chamber 122 formed centrally in it, the radially outermost surface of this chamber 122 including the third area'of the vane to which fluid-pressure is applied, as will be explained. The chambers 122 of the vanes are interconnected by a passageway 123(FIG. 6) formed entirely within the rotor, so that the pressure in all of the chambers 122 is substantially equal at all times. As indicated, the diagonal bores 115 do not intersect thepassa'geway 123. Thus, the passageway 123 will be fed by the bores 115 when they pass the pressure ports as the rotor rotates.

At its inner end, leading to the chamber 122, each vane 119 has a slot in which a hollow rectangular valve element 124 is slidably sealingly received. The element 124 contains a stepped central bore 125 the upper end of which opens into the chamber 122 in the vane. At the lower end of the valve element 124 a reduced flat end surface 126 at the end of a tapered portion forms a valve with the flat surface 112 of the inner end 111 of the vane slot 110.

In the operation of the construction shown in FIG- URES 6, 6A, and 6B, each vane is pressure balanced over the exposed portions of its inner and outer surfaces by pressure since they are connected through bore 115. This pressure also acts on the valve element 124 and tends to lift it from the surface 112. When the lifting force applied by this pressure to the valve element 124 exceeds the forces which tend to close the valve 112, 126, the valve element is moved outwardly, opening the valve 112, 126, permitting fluid to flow through bore 125 to chamber 122 and into interconnecting passageway 123. Thus, since one or more of the vanes is always in a pressure zone adjacent a pressure port 127, fluid at high pressure is applied through the bore 115 which is then in the pressure zone, a valve 112, 126, passageway 125 into chamber 122, and to the passageway 123 and then to chamber 122 of every vane, thereby resiliently maintaining the vanes not in a pressure zone in sealing engagement with the cam surface 106. This sealing engagement is particularly important while the vanes traverse the trans fer zones between the suction and pressure ports. When the pressure in chamber 111 is less than that in chamber 122, as is the case when the vane is in a transfer zone or a suction zone, the pressure in chamber 122 holds. the check valve 112, 126 closed thereby preventing the escape of fluid from passageway 123. Springs 129 in the bores 125 tend to hold the valves 112, 126 closed against the centrifugal force which acts on them as the rotor rotates.

It will be seen that the construction shown in FIG- URES 6, 6A and 6B, like that described in FIGURES 1-5, includes means adapted to be exposed to pressure to urge the vanes outwardly, passageways interconnecting such means including portions rotating past the pressure port, and that escape or loss of pressure in such passageway means to zones of lower pressure is prevented by valve means which open only to admit pressure from the pressure zones and which are closed at all other times.

The rotor assembly shown in FIGURE 7 illustrates still another type of rotor, vane and valve element construction. The rotor 130 is assembled from a splined central portion 136a which is pressed into an outer portion 130]) and interlocked therewith by a dowel pin 132. A groove 133 is formed on the inner surface of rotor portion 13%, and this groove is closed by the central portion 130a. A plurality of radial bores 134 open at their inner ends into this groove 133, and each bore 134 slidably receives a spool-type valve element 135.

The spool valve element 135 has grooves 136 formed on its side surface which do not extend the full length of the element. These grooves 136 defined spool-type valves with groove 133 for governing the admission of fluid from the inner ends 137 of the vane slots to groove 133. The outer end of valve element 135 abuts the inner end 140 of the vane 141 and applies thereto the force created by the fluid pressure in groove or interconnecting passageway 133 acting on the inner end of the element 135. Thus, it will be seen that the operation of this piston valve element is generally similar to that described in relation to FIGURES 15, except that the valve, rather than being a poppet valve, is a spool valve. Ordinarily, in pumps equipped with hydraulic means for vane control there is no need for vane control springs, although they may be used. However, if the fluid pressure translating device is to be used as a motor, fluid pressure to actuate the vane control means may not be supplied if the vanes are not initially in contact with the cam ring, since the fluid may simply bypass across the vane tips directly from the pressure port to the discharge port. To establish initial contact of the vane with the cam ring in order to eliminate this possibility, it is desirable to use springs in combination with the third area actuating means. Also, in a motor, while the vanes traverse the pressure inlet port the vanes must move radially outward and the vane control surfaces are substantially in hydraulic balance, the springs will supply the necessary outward force to keep the vane tips in contact with the cam ring until the vanes pass beyond the pressure inlet zone, at which time the hydraulic vane control will provide additional force to assist the springs in maintaining the vanes in sealing engagement with the cam ring.

FIGURE 8 shows a fragment of an assembly similar to that seen in FIGS. l5 in which a pair of springs 143 are included for this purpose. The springs are received at one end in the rotor 146, and are received at their other ends in bores 144 in the vane 147. The bores 144 in the vanes 147 may be extended through the vanes to the upper end 148 thereof, in order to provide for equalizing pressure on the upper end of the vane with the pressure in the inner end 149 of the vane slot. Springs for this purpose may also be employed in any embodiment of this invention, including that shown in FIGS. 1 through 5. Although not illustrated, when the device is used as a motor, it may be desirable also to provide spring means for lightly urging the valve elements in an outward direction to cause them to follow the vanes closely as they stroke outward when traversing the pressure inlet port.

It may also be desirable to connect the piston valve means with the vane as exemplarized in FIG. 8 wherein one end of the piston valve 150 extends into a T-shaped slot 151 formed in the vane 147. The T-shaped slot provides oppositely disposed lips 152 which extend and fit loosely into a groove 153 in and adjacent the end 154 of the piston valve 150. The end 154 of the piston valve 150 cooperates with a surface 155 within the T-shaped slot to provide the necessary check valve. It will, of course, be obvious that other types of lost motion connectors may be employed for loosely interconnecting the piston valves and vanes. This provides a safety factor insuring that the pin will always remain in close proximity to the vane surface with which it forms the valve.

In place of the means shown in FIGS. 1-5 for closing the passageway 89, the embodiment of FIG. 8 is provided with an annular internal groove 156 inwardly of the passageway 157. This groove 156 is closed and sealed by a flexible rubber or plastic sealing member 158, which is held in place by a plurality of turns of a flat metal spring element 159.

From the foregoing it will be obvious to those skilled in the art that by this invention we have provided a fluid pressure energy translating device including the three area principle described in the previously mentioned Adams et al. patent wherein there is no material volumetric loss of fluid from that portion of the passageway means which is constantly pressurized to act upon the third area means and that the valve means in the passageway means open only when necessary to maintain pressure in the constantly pressurized portion of the passageway means and that the valve means need only open slightly to accomplish this function.

Having described our invention, what we claim is:

1. In a fluid pressure energy translating device,

a casing having side and peripheral walls forming a rotor chamber with circumferentially spaced low and high pressure ports in low and high pressure zones,

alternate transfer and sealing zones between said ports,

a rotor supported for rotation in said chamber,

vanes mounted in vane slots in said rotor, said vanes and rotor cooperating with said side and peripheral aaasg-oea 121 walls to form fluid'tra'nsfer pockets in said transfer "zones, piston means for each vane movable with respectithercto, each of said piston means having a piston end exposed to fluid under pressure'to urge said vane toward one of said walls,

7 passageway means within said rotor interconnecting 2. In a fluid pressure energy translating device,

a casing having side and peripheral walls forming a rotor chamber with circumferentially' spaced low and hig'h'pressure ports in high and low pressure zones, alternate transfer and sealing zones between said'ports,

' a rotor supported for rotation in said chamber,

vanes mounted in vane slots in said rotor, said vanes and rotor cooperating with said side and peripheral walls to form fluid transfer pockets in said transfer zones,

a hollow piston for each vane and movable with re- "spect' thereto, each said hollow piston having opposite ends, the first of said opposite ends being-exposed to' fluid under pressure to cause said hollowpiston to urge said vane toward one of said walls, the other of said ends cooperating withsaid vane to form a pressure operated check valve,

passageway means within the rotor interconnecting said first ends of said hollow pistons,

-said check valves communicating sequentially with'said high pressure zone as said rotor rotates,

said check valves formed by said pistons and said vanes being'opened bypressure from said high pressure zone when communicating therewith when the pressure in said high pressure zone is higher than the pressure acting one the first ends of said hollow pistons and being closed except when admitting pressure from said high pressure zone.

3. In a hydraulic'fluid pressure energy translating device of the vane type, structure for hydraulically controlling the operation of the vanes thereof,

said fluid'pressure energy translating device including a casing having a rotor chamber and low and high pressure ports in low and high pressure zones,

a rotor supported for rotation in said chamber, said rotor being disposed relative to a cam surface forming wall of saidchamber to provide a fluid transfer section between said low and high pressure zones, -said rotor having vane slots,

vanes disposed for reciprocatory movement in said slots inderiendently of eachother, each of said-vanes'having sealing means on one end engaging the cam surfaceforming 'wall'of said chamber and surface means thereof presenting a first area to hydraulic pressure'which urges said vane inwardly in its slot,

means on each'of 'saidvanes presenting a second area to hydraulic pressure for urging said vane outwardly in its slot,

a 'passage for supplying fluid at substantially equal pressure at'all times to the first and second area of each vane,

means associated with each vane presenting a third area to hydraulic pressure for urging said vane outwardly in its slot, said third area being the smallest of said areas,

a chamber contained entirely within said rotor interconnecting allof said means presenting a third area,

aplu'rality of conduit means in said rotor connected 12 with said"chaniber,each'said conduit means including an open outer end passing through said high and low-pressure zones sequentially as said rotor rotates, and a pressure operated check valve in each said conduit means between its outer ends and saidchamber which is opened by pressure-from said high pressure zone to admit pressure directly from said high'pressure zone through'sai d rotor to said chamben said check valves being closed by pressure in said chamber except --when admittingpr'essure theretofrom said high pressure zone, each said check valve permitting flow through it only in the direction away'from said'high pressurezone to-said chamber, the hydraulic forces on the'third area associated with --each vane urging 'the'vane outwardly in its'slot and against the cam surface forming wall of said chamber. -4. In a fluid pressure energy translating device,

a casing having side and peripheral walls forming a rotor chamber with circumferentially spaced'low and high pressure zones, alternate transfer and sealingzones between said zones, a rotor supportedfor rotation in said chamber, vanes having radially inner and outer ends,'said vanes being mountedin vane slots in said rotor and engaging said side and peripheral walls to form fluid transfer pockets, means for substantially balancingthe pressure forces on the inner and outerend of each vane at all times, a piston associated with each vane which is adapted to be exposed to fluid under pressure to urge the vane outwardly, passageway'means'formed entirely within said rotor interconnecting all of said pistons-and equalizing the pressure acting thereon which pressure urges said vanes outwardly, passageways in said rotor leading to said-passageway means, said'passageways opening to a surface of said rotor at angularly spacedpositions thereon and communicating serially with said high pressure zone as said rotor rotates, and a pressure responsive check valve in each said passageway in said rotor opening to admit fluid therethrough directly into said passageway means when the pressure at the opening of said passageway to the surface of said rotor substantially exceedsthe pressure in said passageway means, each said check valve permitting flow through it only in the direction toward said passageway means. 5. In a vane type fluid pressure energy translating device including a rotor having a plurality of vanes mounted for relative radial movement, a stator presenting a cam surface for engagement by'the outer'ends of said vanes, fluid transfer pockets being defined between said vanes, means for-applying substantially equal pressure at all times to the outer end of a vane and to the inner end of the vane, and a pressure port and a suction port at circumferentially spaced positions between said-rotor and said cam surface,

the improvement comprising, means for applying I a fluid pressure created force to said vanes to hold the same radially outward ine'ngagement with said cam surface,- comprising,

"pressure operated pistons mounted in said rotor for movemen't'into abutting relation with the inner ends of the respective vanes,

lost 'motion means loosely'interconnecting each said piston to the respective vane permitting only limited separation of said piston from said vane,

a fluid passage contained wholly Within said rotor for applying pressure to the inner ends of said pistons to urge the same into abutting relation withthe respective vanes and thereby urge the vanes outwardly,

arid a'plurality'of'passage meanswholly within said rotor communicating between said fluid passage and the respective fluid transfer pockets,

each said passage means including structure forming a pressure operated check valve for admitting fluid under pressure directly from the respective fluid transfer pocket through said rotor into said fluid passage and for preventing flow in the opposite direction.

6. In a vane type fluid pressure energy translating device including a rotor having a plurality of vanes mounted in vane slots for relative radial movement, a stator presenting a cam surface for engagement by the outer ends of said vanes, means operative at all times to equalize pressure on the outer end of each said vane with that in its vane slot, and pressure and suction zones at circumferentially spaced positions between said rotor and said cam surface,

the improvement comprising,

means for applying a fluid force to said vanes to hold the same outwardly in engagement with said cam surface, said means comprising,

a radial bore in said rotor extending inwardly from each vane slot,

a tubular member slidably mounted in each bore, said tubular member forming a pressure operated check valve with the inner end of the vane in said slot governing the How of fluid from said vane slot through said tubular member,

a closed fluid chamber defined wholly within said rotor interconnecting the said bores at the inner ends of said tubular members,

the check valve between said tubular member and the inner end of said vane being opened by pressure in said slot externally of said tubular member in excess of the pressure in said chamber, said check valve permitting flow through it only in the direction toward said chamber.

7. In a vane type fluid pressure energy translating device including a rotor having a plurality of vanes mounted in vane slots for relative radial movement, a stator presenting a cam surface for engagement by the outer ends of said vanes, means for equalizing pressure on the outer end of each said vane with that in its vane slot, and pressure and suction zones at circumferenti-ally spaced positions between said rotor and said cam surface,

the improvement comprising,

means for applying a fluid force to said vanes to hold the same outwardly in engagement with said cam surface, said means comprising,

a radial bore in said rotor extending inwardly from each vane slot,

a tubular member slidably mounted in each bore, said tubular member having an outer end area forming a pressure operated check valve with the inner end of the vane in said slot governing the flow of fluid from said vane slot through said tubular member, a fluid chamber defined within said rotor interconnecting the said bores at the inner ends of said tubular members,

the check valve between said tubular member and the inner end of said vane being opened by pressure in said slot externally of said tubular member in excess of the pressure in said chamber when said vane is in said pressure zone, said check valve permitting flow through it only in the direction toward said chamber.

8. In a vane type pressure energy translating device including a rotor having a plurality of vane slots mounting vanes for relative radial movement, a stator presenting a cam surface for engagement by the outer ends of said vanes, passage means for equalizing pressure in each vane slot with that acting on the outer end of the vane therein, and pressure and suction zones at cirumferentially spaced positions between said rotor and said cam surface,

the improvement comprising,

pressure operated piston means for applying a force to said vanes to hold the same outwardly in engagement with said cam surface, said means comprising,

at least one bore in said rotor extending inwardly from each vane slot,

a piston slidably mounted in each said bore for movement into contact with the inner end of the vane in the slot,

a fluid passage defined within said rotor interconnecting the said bores inwardly of the inner ends of said pistons,

and means forming a pressure operated spool type check valve between each said piston and its bore which check valve is opened by pressure when the pressure in said vane slot exceeds the pressure in said passage to admit fluid to said passage, said check valve being closed by pressure in said passage and said piston being held against the inner end of the vane when the pressure in said passage exceeds the pressure in said vane slot, said check valve permitting flow through it only in the direction toward said passage.

9. In a fluid pressure energy translating device,

a casing having side and peripheral walls forming a rotor chamber with circumferentially spaced suction and pressure zones,

a rotor supported for rotation in said chamber,

pressure balanced vanes mounted in vane slots in said rotor, said vanes engaging said side and peripheral walls to form fluid transfer pockets, each of said vanes including means for conducting the pressure at the outer end of the vane to the inner end of the vane in the vane slot,

each vane having a chamber formed in it which is closed by said vane slot,

a passage in said rotor connecting said chambers,

a guideway in each vane extending from the inner edge of the vane to the chamber in said vane,

a sliding valve element in each said guideway having a longitudinal passage for admitting fiuid pressure from the vane slot into the chamber of said vane,

and means presenting a fixed surface which forms a pressure operated check valve with said valve element for closing said longitudinal passage to the flow of fluid therethrough when the pressure in said chamber is greater than that in said vane slot.

10. In a hydraulic fluid pressure energy translating device of the vane type, structure for hydraulically urging the vanes of said device outwardly,

said fluid pressure energy translating device including a casing having a rotor chamber and low and high pressures zones,

a rotor in said chamber, said rotor being disposed relative to the peripheral wall of said chamber to provide a fluid transfer section between said low and high pressure zones, said rotor having substantially radially extending vane slots,

a shaft connected to said rotor and supporting said rotor for rotation in said chamber,

vanes disposed for reciprocatory movement in said slots independently of each other, each of said vanes having sealing means on its radially outer end engaging the peripheral wall of said chamber, surface means on the outer end of each vane presenting a first area to hydraulic pressure which urges said vane inwardly in its slot,

surface means on the inner edge of each vane presenting a second area to hydraulic pressure for urging said vane outwardly in its slot,

means for supplying fluid at substantially equal pressure to the first and second area of each vane, means associated with each vane presenting a third area to hydraulic pressure for urging said vane outwardly in its slot, said means comprising a piston mounted in a radial vbore in the rotor ,forsliding movementinto abuttingtengagement with the inner endof ,each vane, said piston having a bore extending from end toend thereof and a' peripheral recess around itsouter end,

passageway means Within said rotorjor conducting fiuid atrequalpressures at alltimes tothe inner ends of all .of said pistons, said passageway .means being formed by' an annular internal groovein t11e,rotor and .a ,member closing said-g ve, vs i memb "encircling. .said shaft,

the inner ends of said vane slots communicating with saidhightp esnurehzone as said rotqrirotates,

the outer endrof each ,said piston fforming ,a pressure .pperated. ,check valve withntheinncrend of the vane .which valve opens, to ,admitpressnre from said high pressure zo ne I50 usaidtpassageway means, said valve being ,c1os,e.d except when admitting pressureirom said high pressure. zone,

the hydraulic forces on the third area associated with each vane ,ovelihalanc ng ;the;hydr;aulic forces on the first ,areaofthe .vane andurging the vane outwardly in its slot and against the peripheral wall of said chamber while said vane traversessaid fluid transfer section.

11.,In,.a hydraulic fluid pressure ,enfilfgy translating device,

a casing .havin'g ,side and peripheral wallsjformjng a rotor ,chamber rwith.circurnferentiallyispaced'low and high pressureports in low and high pressnreuzones 1 respectively, arotor supported, for rotationin saidchambe ,vanesmounted i-in, va ne,s1ots in said rotor,,said ,vanes means defining a first area on the outer end of each vane,

means defining a second area on each vane opposed to the first area on said vane,

means defining athird area in an internal slot in each vane, said third area also being opposed to'the first area on said vane,

a passageway for conducting fluid atequal pressures to the first and second areas o feach vane,

means forming a chamber entirelywit-hin the rotor interconnecting all of the-third areas in the'internal slots of ,said vanes,

,and a plurality of fluid supply passageways entirely within said'rotor-for delivering fluid under pressure to said chamberfrorn a-hi'gh pressure-zone of said rotor chamber directlythrough said rotor, each said supply passageway including -a pressure -operated check valve permitting flow in said supply-passageway toward said chamber but not in the opposite direction.

References Cited by theExaminer UNITED STATES PATENTS 674,258 5/1901 Croston 103-136 720,993 2/ 1903 Allen 103-136 920,976 5/1909 Minor 103-136 1,093,005 4/1914 Myers 103-136 2,360,420 11/1944 Tucker etal 103-136 2,967,488 l/1961 Gardiner 103-136 2,967,489 1/:l961 Harrington 103-136 3,102,493 9/1963 Davin 103-135 J. ALBRECH Prim y. E am ner- ,35 JOSEPH 'H. BRANSON, JR., ROBERT VARGO,

Examiners. 

1. IN A FLUID PRESSURE ENERGY TRANSLATING DEVICE, A CASING HAVING SIDE AND PERIPHERAL WALLS FORMING A ROTOR CHAMBER WITH CIRCUMFERENTIALLY SPACED LOW AND HIGH PRESSURE PORTS IN LOW AND HIGH PRESSURE ZONES, ALTERNATE TRANSFER AND SEALING ZONES BETWEEN SAID PORTS, A ROTOR SUPPORTED FOR ROTATION IN SAID CHAMBER, VANES MOUNTED IN VANE SLOTS IN SAID ROTOR, SAID VANES AND ROTOR COOPERATING WITH SAID SIDE AND PERIPEHRAL WALLS TO FORM FLUID TRANSFER POCKETS IN SAID TRANSFER ZONES, PISTON MEANS FOR EACH VANE MOVABLE WITH RESPECT THERETO, EACH OF SAID PISTON MEANS HAVING A PISTON END EXPOSED TO FLUID UNDER PRESSURE TO URGE SAID VANE TOWARD ONE OF SAID WALLS, PASSAGEWAY MEANS, WITHIN SAID ROTOR INTERCONNECTING SAID PISTON ENDS, SAID PASSAGEWAY MEANS INCLUDING 